Change color for some symbols in a sylable

[Светлана]

Hello all!
I make notes for old Russian church music. Before I just learned lilypond, now 
I'm concerned with look and feel, so I have quite many questions. I'll try to 
ask them one by one, not making mess with multiple topics in one message. If 
it's not the right way here, please tell me.

One thing that I need is coloring symbols inside lyrics. I use lyrics for old 
notation (called znamennoye in Russian), it makes sense because it uses 
syllables and is being typed as symbol strings with a special font. One 
syllable (znamya) in common font could look like "*8ъйяХ1-" or something like 
that.

Some symbols in a syllable (not all the syllable) should be colored in red. 
When I use markup it is applied to all the syllable, which is wrong for me. How 
could I color just certain symbols? The best thing would be a script that tells 
that, for example, all "o"s and "-"s must be red if lyrics is entered in 
\lyricmode, not in \lyricsto, because there should be some normal text. The red 
symbols are always the same but it must be case sensitive, use cyrillics 
(unicode) and special symbols (%/|\ etc.).

Here is some example how it looks like: 
http://imageshack.us/photo/my-images/641/znamennoye.png/

Regards,
Svetlana.